Start by clearing the first line, then work your way up to the top. Don't worry about clearing excess lines, only the "target lines" which are highlighted white. For all the other space, just fill it up so you can build higher lines. With a few rounds of practice, you'll have it down to fill excess lines aiming to build up to clear the white lines. Once you get to the white "target lines" fill with all shapes as quickly as possible. At the top, fill "target line" quickly and don't fill over the screen or the game will end.

I got Silver at 1:12. You may curse the screen a few seconds because it takes that amount of time to pop after you end the round, but eventually it'll pop.

Hope this review helps, I'm aiming to clear a few more cheevos in Tetris and may end up writing a few more reviews along the way.